Ribbon feeding device for typewriting machine



R. GATHER 3,02

RIBBON FEEDING DEVICE FOR TYPEWRITING MACHINE March 27, 1962 Filed Sept. 15, 1960 2 Sheets-Sheet 1 Fig.7

Fig. 2

/nuenf0/ 20a0/fi9a/her 73 R. GATHER March 27, 1962 RIBBON FEEDING DEVICE FOR TYPEWRITING MACHINE 2 Sheets-Sheet 2 Filed Sept. 15, 1960 Fig.5

Fig.3

//7 (re/7 for 800/04 202% er 5' 3,026,987 RIBBQN FEEDING DEVHE 1 R TYPEWRITENG MACHINE Rudoif Gather, 61 Mulgaustrasse, Rheydt- @denisirchen, Germany Filed ept. 13, 19st), Ser. No. 55,644 4 Claims. (6!. 197-153) This invention relates to a device for providing a ribbon feed in a typewriting, tabulating or like machine. The invention has been developed in connection with providing a device which can be used as an attachment for an existing machine (as is specifically referred to hereinafter) but it will be understood that the invention is not limited to this case as it may also be incorporated in a typewriting or like machine as part of the original machine itself.

As an attachment for an existing machine the present invention aims at increasing the copying capacity of the machine. In a typewriting or like machine there is the usual ribbon for producing the top copy and then further copies are produced by the use of appropriate carbon papers or webs but there is a limit to the number of carbon copies which can be produced in this way, this limit being dictated by the thickness of the composite paper web passing round the platen of the machine, and with existing machines four or five carbon copies is the maximum which can be satisfactorily produced. An attachment incorporating the present invention would provide one or more extra runs of ribbon to produce further copies without the use of extra carbon paper.

According to the present invention I provide a device for feeding a ribbon in a typewriting, tabulating or like machine comprising a pair of spools upon which a ribbon is wound and which act in alternation as supply spool and take-up spool, power operated means for selectively driving one or the other of said spools independently of the typing action of the machine, and means for automatically reversing the direction of feed of the ribbon when the currently-acting supply spool is about to become exhausted.

The driving means may comprise an electric motor and the automatic reversing means may comprise an electric switching device which is actuated by means of engagement by one or the other of two trigger pieces carried by the ribbon, one near each end of the ribbon.

In order to maintain the ribbon taut during its feeding movement a braking device may be provided adapted to operate so as to exert a braking effect upon whichever spool is for the time being acting as the supply spool and is being rotated by the ribbon being pulled therefrom.

According to a further aspect of the invention I provide a device for feeding a ribbon, asan attachment for a typewriting, tabulating or like machine, comprising an attachment bar adapted to be mounted upon the machine adjacent to the platen thereofand having at its ends brackets carrying ribbon guidesv through and around which the ribbon is trained, and a, casing supported from one end of said attachment bar, said casing carrying a pair of spools upon which a ribbon is wound and which are p d to a t lternately astake-up and supply spools, power-operated means for selectively driving one of the other of said spools independently of the operator of the machine and means for automatically reversing the direction of travel of the ribbon when the currently-acting supply spool is almost exhausted.

Other features and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description of a preferred embodiment when considered in connection with the accompanying drawing in Bfiihfid? Patented Mar. 27, 1962 which like reference numerals designate like parts throughout the figures thereof, and wherein:

FIG. 1 shows an embodiment of the invention inside elevation;

FIG. 2 is an enlarged view of a portion of the device of FIG. 1;

FIG. 3 illustrates the apparatus of FIG. 2 in plan view;

FIG. 4 is a fragmentary side-elevational view of the apparatus of FIG. 2; and

FIG. 5 is a front elevation of the apparatus of FIG. 2.

The example of the invention shown in the drawings is in the form of a device which can be attached to an existing machine, which may for example, be a tabulating machine, and for this purpose there is provided for the device an elongated attachment bar it) having detachable end parts 11 by means of which the complete device can be mounted upon a tabulating machine so as to position it adjacent to the platen roller 1 of the machine shown in FIG. 1.

At one end, the attachment bar It has a bracket 12 which at the top is provided with a member 13 around which the ribbon 14 is trained to reverse its direction of movement and at the other end th attachment bar has another bracket 15 provided at its upper end with a ribbon guide 16 which may be of any convenient form and is adapted to be opened to separate the outgoing and incoming lengths of ribbon when the attachment is being set up and copy paper is being inserted in the machine to pass between the two runs of the ribbon.

The bracket 15 has secured thereto a suitably shaped arm 17 and to the outer end of the arm 17 the gear box and driving unit 18 is Secured.

The unit 18 may be completely enclosed in a suitable casing which is not shown in the drawings and on the exterior of this casing the controls for the device may be mounted and such controls may include an electric switch for the supplyof current and a speed controller for the driving motor.

The gearing of the device is mounted between a pair of spaced plates 26 at the rear and 21 at the front, these being secured to the arms 17 and in FIG. 3ythedriving motor is indicated generally at 22.

The output shaft from the driving motor is indicated at 19 and has fixed thereon a pinion 23 which is in constant mesh with a pinion 24 carried between the arms of a yoke 25 which is pivoted about an axis of the shaft 1? so that the pinion 2 4 swings about the axis.

The two spools for the ribbon are shown at 26 and 27 and each spool is driven by its associated shaft by means of one or more projecting studs 28 carried by flanged collar 29 secured to the shaft, the shaft end being arranged for a suitable type of spring retaining clip. The shaft for spool 26 is shown at 3% and the shaft for spool 27 is shown at 31 in FIG. 3.

Referring to FIG. 5 the shaft 3% has fixed thereon a gear wheel 32 which has as its rear face a friction surface, forming one half of a slipping clutch the other half of which is formed by the friction disc 33 fixed to spacer disc 34 in turn fixed to gear wheel 35 which is 'slidable p the s a 3 a d isloo e y m u ted th Friction disc 33 and gear wheel 32 are pressed resiliently together by means of the spring arm 36 which is anchored at its lower end to the rear plate 20 and the spring pressure of which can be adjusted by means of the adjusting screw 37. The shaft 31 of the other spool has fixed thereon a gear wheel 38 and a further gear wheel 39 which is in mesh with the gear Wheel 35.

Two toggle switches 4d are indicated in FIG. 3 for controlling the direction of rotation of the driving motor 22 and these are adapted to be operated by switch arms 41 fixed upon a spindle 42 which extends through the two plates 29 and 21 and in front of the gear box has fixed thereon a rocker arm 43 which at its upper and lower ends carries ribbon guides 44-.

The ribbon 14 is passed over a plurality of guide rolls 46 and through the guides 44 and near each end of the ribbon there is fixed a trigger member which consists of a small piece of metal 45 which may pass over the rolls 46, but is too thick to pass through the ribbon guide 44 so that when one spool is exhausted the trigger 45 engages the guide 44- thus rocking the rocker arm 43 and causing the spindle 42 to turn and by means of the arms 41 operate the appropriate toggle switch to reverse the direction of rotation of the driving motor.

Considering the position shown in FIG. 2 it will be observed that the yoke 25 is across to the left so that pinion 24 is meshing with the gear wheel 32 and thus the spool 26 is acting as the take-up spool and is being driven, while the ribbon 14 is being drawn off the other spool 27 which is acting as the supply spool and the position has been reached where the trigger member 45 is about to engage the ribbon guide 44. Under these conditions the spool 27 is being driven in the same direction as the spool 26 and thus the gear wheel 39 is being driven in this direction and is therefore rotating the gear wheel 35 in the opposite direction. Hence friction disc 33 is rotated in the opposite direction to the friction face on gear wheel 32 and therefore a braking effect is transmittted to the supply spool 27 thus ensuring that the ribbon is maintained taut as it is pulled off spool 27.

When the trigger member 45 engages ribbon guide 44 and the drive is reversed rotation of pinion 23 is reversed and thus causes the yoke 25 to swing to the right and bring pinion 24 into mesh with gear wheel 38 as shown in FIG. 4. Thus spool 27 now becomes the take-up spool and being positively driven and spool 26' becomes the supply spool driven in the same direction. Gear wheel 39 is driving gear wheel 35 in the opposite direction so that again the friction disc 33 and friction face on gear wheel 32 are rotated in opposite directions and a braking effect is being exerted upon spool 36 to retain the ribbon taut as it is drawn on the spool.

The movement of the ribbon and reversing of its direction of movement is therefore independent of the typing operation being performed by the machine.

It should be understood, of course, that the foregoing disclosure relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the example of the invention herein chosen for the purpose of the disclosure which do not constitute departures from the spirit and scope of the invention set forth in the appended claims.

What I claim and desire to be protected by Letters Patent of the United States is:

1. A device for feeding a ribbon in a typewriting machine and the like, comprising a support; a pair of spools rotatable on said support; a ribbon wound on said spools, said ribbon having two ends respectively secured to said spools whereby said spools act as a supply spool and a take-up spool respectively; electrically operated driving means; switch means sensitive to the amount of said ribbon on one of said spools for reversing the direction of driving movement of said driving means; and means responsive to reversal of said direction of movement for alternatingly engaging said driving means with one of 4 said spools for rotation thereof independent of the typing action of said machine.

2. A device for feeding a ribbon in a typewriting machine and the like, comprising a support; two shafts rotatable on said support; a pair of spools respectively mounted on said shafts for rotation therewith; a ribbon Wound on said spools, said ribbon having two ends respectively secured to said spools whereby said spools act as a supply spool and a take-up spool respectively; two friction discs mounted on said support for joint rotation With said shafts; resilient means for permanently urging said friction discs into braking engagement; power operated driving means; and means sensitive to the amount of said ribbon on one of said spools for alternatingly engaging said driving means with one of said spools for rotation thereof independent of the typing action of said machine.

3. A device for feeding a ribbon in a typewriting machine and the like, comprising a support; two shafts rotatable on said support; a pair of spools respectively mounted on said shafts for rotation therewith; a ribbon wound on said spools, said ribbon having two ends respectively secured to said spools whereby said Spools act as a supply spool and a take-up spool respectively; two friction discs mounted on said support for joint rotation with said shafts in opposite directions when said spools rotate to unwind said ribbon from the supply spool and to wind it on the take-up spool, said friction discs having radially extending friction faces; resilient means for permanently urging said friction faces into braking engagement; power operated driving means; and means sensitive to the amount of said ribbon on one of said spools for alternatingly engaging said driving means with one of said spools for rotation thereof independent of the typing action of said machine.

4. A device for feeding a ribbon in a typewriting machine and the like, comprising a support; two shafts rotatable on said support; a pair of spools respectively mounted on said shafts for joint rotation therewith; a ribbon wound on said spools, said ribbon having two ends respectively secured to said spools, whereby said spools act as a supply spool and a take-up spool respectively; two friction discs mounted on said support for joint rotation with said shafts in opposite directions when said spools rotate to unwind said ribbon from the supply spool and to wind it on the take-up spool, said friction discs having radially extending friction faces; resilient means for permanently urging said friction faces into braking engagement; electrically operated driving means; switch means sensitive to the amount of said ribbon on one of said spools for reversing the direction of driving movement of said driving means; and means responsive to reversal of said direction of movement for alternatively engaging said driving means with said one spool for rotation thereof independent of the typing action of said machine.

References Cited in the file of this patent UNITED STATES PATENTS 2,419,369 Ritzert Apr. 22, 1947, 2,636,590 Rice Apr. 28, 1953 2,695,698 Henry Nov. 30, 1954 2,789,676 Grundel Apr. 23, 1957 2,803,331 Berill Aug. 20, 1957 2,872,016 Sharp Feb. 3, 1959 

